LAUSR

Double-shelled nanostructure ZnO/TiO2/CdS was successfully prepared via a two-step layer-by-layer absorption and reaction method and the successive ionic layer adsorption reaction approach. The obtained photoelectrodes were characterized by field emission scanning electron microscopy, X-ray diffraction, high resolution transmission electron microscope, energy-dispersive spectroscopy and UV–Vis diffuse reflectance spectroscopy techniques, respectively. The optimized ZnO/TiO2/CdS ternary hetero-structured electrode generates a photocurrent density of 5.8 mA/cm2, which is approximately 25 and 20 times higher than that of pure ZnO and ZnO/TiO2 nanorod arrays. This superior photoelectrocatalytic performance attributed to the improved visible light absorption and charge separation ability. Methyl orange (MO) decoloration ratio of 71.3% was obtained in 40 min when ZnO/TiO2/CdS was used, while a higher efficiency of 97.5% for MO decoloration can be achieved by using an anodic bias of 0.2 V versus Ag/AgCl. This work opens a door to the design of ternary nanostructured materials ZnO/TiO2/CdS nanorod arrays with high photoelectrocatalytic ability.